643466 has 4 divisors (see below), whose sum is σ = 965202. Its totient is φ = 321732.

The previous prime is 643463. The next prime is 643469. The reversal of 643466 is 664346.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (643463) and next prime (643469).

It can be written as a sum of positive squares in only one way, i.e., 570025 + 73441 = 755^2 + 271^2 .

It is not an unprimeable number, because it can be changed into a prime (643463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160865 + ... + 160868.

2⁶⁴³⁴⁶⁶ is an apocalyptic number.

643466 is a deficient number, since it is larger than the sum of its proper divisors (321736).

643466 is a wasteful number, since it uses less digits than its factorization.

643466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321735.

The product of its digits is 10368, while the sum is 29.

The square root of 643466 is about 802.1633250155. The cubic root of 643466 is about 86.3326757485.

The spelling of 643466 in words is "six hundred forty-three thousand, four hundred sixty-six".